Ferroelectric local field regulated and controlled one-dimensional / two-dimensional heterojunction photoelectric detector and preparation method thereof

Abstract

The invention discloses a ferroelectric local field regulated one-dimensional / two-dimensional heterojunction photoelectric detector and a preparation method thereof, and belongs to the technical field of photoelectric detector preparation. The detector structure comprises a SiO2 / Si substrate, a one-dimensional Te nanowire layer, a two-dimensional MoS2 layer and two electrodes, wherein the one-dimensional Te nanowire layer is arranged on the SiO2 / Si substrate and serves as a P end, the two-dimensional MoS2 layer serves as an N end, the two electrodes are arranged at one end of the one-dimensional Te nanowire layer and one end of the two-dimensional MoS2 layer, and ferroelectric layers are arranged on the upper surfaces of the one-dimensional Te nanowire layer and the two-dimensional MoS2 layer; and a transparent conductive layer is arranged on the upper surface of the ferroelectric layer. According to the structure disclosed by the invention, after the ferroelectric layer is polarized, a ferroelectric local field is generated to deplete carriers in a channel, so that channel dark current is effectively reduced, responsivity and detectivity are improved, and high-performance photoelectric detection from visible to near-infrared bands is realized.

Description

Technical Field

[0001] The invention relates to the field of low-dimensional heterojunction semiconductor photoelectric detection devices, and in particular to a one-dimensional / two-dimensional heterojunction photoelectric detector regulated by a ferroelectric local field and a preparation method thereof. Background Art

[0002] Photodetectors are photoelectric sensors that can convert light signals into easily measurable electrical signals such as current and voltage. They are widely used in daily life and national security, such as communications, environment, health, and national defense. In particular, wide-spectrum detection detectors that can achieve low dark current and high detection are urgently needed for industrial applications.

[0003] In the field of photoelectric detection, traditional semiconductor thin film detectors (such as Si, HgCdTe, InGaAs and InSb, etc.) have always dominated the photoelectric detection market. With the development of the times, the next generation of photodetectors is developing towards wide-band, high-sensitivity detection, ultra-small size, large-array imaging and multi-spectral detection. In recent years, emerging one-dimensional / two-dimensional materials have been widely used in the field of photoelectric detection. Since there are no dangling bonds on the surface of two-dimensional materials and weak van der Waals force interactions between layered structures, two-dimensional materials can be stacked in any order like Lego blocks to create various types of van der Waals heterostructures. For the detection of infrared light, materials with small band gaps (such as black phosphorus, tellurium, etc.) are generally used, but narrow band gap materials have large dark currents at room temperature, which reduces the photoelectric detection degree. The industry uses a stack of P-type materials and N-type materials to construct a PN heterojunction to achieve low dark current detection, such as WS2 / MoS2 heterojunction and MoTe2 / MoS2 heterojunction. However, for infrared photoelectric detection, the use of heterojunctions composed of narrow bandgap materials cannot effectively reduce the dark current to achieve low dark current detection from visible to infrared. The two-dimensional Te or one-dimensional Te nanowires reported in the literature can be used for infrared detection, but their dark current is very large, resulting in reduced detection.

[0004] In existing literature, the carrier transport characteristics of the channel material are usually regulated by changing the size and direction of the back gate voltage. However, the gate voltage provided by the ordinary gate dielectric layer requires uninterrupted power supply on the one hand, and the local field effect provided on the other hand is limited. Therefore, it is a feasible way to seek a combination of low-dimensional materials and other functional materials to improve the overall performance of the detector.

[0005] Ferroelectric materials have the characteristics of spontaneous polarization. Spontaneous polarization can be oriented in a consistent manner under the action of an electric field, and the polarization direction can be reversed with the reverse direction of the external electric field. After the external electric field is removed, the residual polarization can exist stably. That is, under the action of an electric field, the polarization orientation is consistent to produce local fields with polarization "upward" and polarization "downward". This method can be used to regulate the carriers in the channel, suppress dark current, and improve photodetection. The surface polarization induction of ferroelectric materials can produce strong local fields with polarization upward or polarization downward. Through the surface local field, it can effectively and continuously act on the atomically thin two-dimensional material, so that the carriers in the channel are depleted or accumulated. Based on this, the ferroelectric polarization local field can be used to regulate the carrier behavior in the channel of low-dimensional material devices, and achieve excellent photodetection performance such as low dark current, low power consumption, and high detection. On the one hand, this ferroelectric strong local electric field can keep the carriers in the channel material in a completely depleted state, and even regulate the band structure of the channel material. On the other hand, the effect of the ferroelectric local field is non-volatile, and the electric field effect remains after the gate voltage is removed, which can reduce the power consumption of optoelectronic devices. Based on the higher polarization electric field in ferroelectric materials and the advantages of low-dimensional materials at the nanoscale, the advantages of low-dimensional materials and ferroelectric materials complement each other, providing opportunities for the realization of new optoelectronic devices.

[0006] The present invention utilizes the polarization electric field generated by ferroelectric materials to regulate heterojunction phototransistors composed of one-dimensional / two-dimensional materials, thereby reducing dark current and improving the detection response rate and detection rate of the device from visible light to near-infrared bands. Summary of the invention

[0007] In order to improve the shortcomings of existing heterojunction photodetectors, the present invention proposes a method for controlling a one-dimensional / two-dimensional heterojunction photodetector using a ferroelectric local field generated by a ferroelectric material and a method for preparing the same. The prepared detector can achieve low dark current, high light response, wide spectrum detection and other performances, expanding the application of low-dimensional materials in the field of photodetection.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is: A one-dimensional / two-dimensional heterojunction photodetector regulated by a ferroelectric local field, the detector comprising a SiO2 / Si substrate, a one-dimensional Te nanowire layer as a P-terminal is arranged on the upper surface of the SiO2 / Si substrate; a two-dimensional MoS2 layer as an N-terminal is arranged on the upper surface of the one-dimensional Te nanowire layer; electrodes are arranged at one end of the upper surface of the one-dimensional Te nanowire layer and one end of the upper surface of the two-dimensional MoS2 layer respectively; a ferroelectric layer is arranged on the upper surfaces of the one-dimensional Te nanowire layer and the two-dimensional MoS2 layer; the ferroelectric layer partially covers or completely covers the electrode, and a transparent conductive layer is arranged on the upper surface of the ferroelectric layer as a top gate. One end of the two-dimensional MoS2 layer is arranged on the upper surface of the one-dimensional Te nanowire layer, and the other end is arranged on the lower surface of the electrode; one end of the one-dimensional Te nanowire layer is arranged on the lower surface of the two-dimensional MoS2 layer, and the other end is arranged on the lower surface of the electrode; the transparent conductive layer does not contact the electrode.

[0009] When the top gate applies voltage to polarize the ferroelectric layer, the generated ferroelectric local field acts on the Te / MoS2 heterojunction channel, regulates the channel carrier current, reduces dark current, and improves photodetection. Due to the non-volatility of ferroelectric materials, the ferroelectric local field always acts on the channel.

[0010] The SiO2 / Si substrate structure is a Si layer with a SiO2 layer on the upper surface, wherein the thickness of the SiO2 layer is 280-320 nm.

[0011] The diameter of the one-dimensional Te nanowire layer is 50-150 nm.

[0012] The thickness of the two-dimensional MoS2 layer is 5~20 nm.

[0013] The electrode is made of gold, silver or aluminum, and has a thickness of 50-100 nm.

[0014] The ferroelectric layer material is a poly (vinylidene fluoride-trifluoroethylene) film or a two-dimensional layered copper indium phosphorus sulfur material (CuInP2S6).

[0015] When the ferroelectric layer material is a poly (vinylidene fluoride-trifluoroethylene) film, the thickness is 300-500 nm; when the ferroelectric layer material is a two-dimensional layered copper indium phosphorus sulfur material (CuInP2S6), the thickness is 10-20 nm.

[0016] The transparent conductive layer material is a graphene thin layer or an aluminum film.

[0017] The thickness of the transparent conductive layer is 5-20 nm.

[0018] The present invention also discloses a method for preparing the above-mentioned one-dimensional / two-dimensional heterojunction photoelectric detector regulated by the ferroelectric local field, comprising the following steps: S1. The MoS2 crystal material and the transparent conductive layer material are respectively peeled off onto the PDMS substrate by mechanical peeling method to obtain MoS2 nanosheets and transparent conductive layer nanosheets; Te nanowire material is grown on the substrate by CVD method, PDMS is bonded to the Te nanowire material, and then separated to obtain a single Te nanowire on the PDMS; S2. Find the one-dimensional Te nanowires and MoS2 nanosheets on the PDMS through the micro-focus transfer system, and transfer the Te nanowires to the upper surface of the SiO2 / Si substrate to form a one-dimensional Te nanowire layer; The PDMS substrate with MoS2 nanosheets was moved just above the one-dimensional Te nanowire layer to cover part of the Te nanowires, thereby obtaining a two-dimensional MoS2 layer and forming a one-dimensional / two-dimensional heterojunction as the channel of the device. The electrodes are transferred to the upper surfaces of the two ends of the one-dimensional Te nanowire layer and the two-dimensional MoS2 layer respectively to serve as the source and drain of the device; S3. The ferroelectric layer was prepared by a spin coating - baking process, where the ferroelectric layer solution was spin coated onto the upper surface of the one-dimensional Te nanowire layer and the two-dimensional MoS2 layer, and then dried to obtain the ferroelectric layer; S4. Use the microscopic focus transfer system to find the transparent conductive layer nanosheet on the PDMS, and move the PDMS substrate with the transparent conductive layer nanosheet to the top of the one-dimensional Te nanowire layer and the two-dimensional MoS2 layer, covering the ferroelectric layer, and covering the one-dimensional Te nanowire layer and the two-dimensional MoS2 layer at the same time, but not contacting the electrode, to obtain a transparent conductive layer. Finally, a one-dimensional / two-dimensional heterojunction photodetector regulated by the ferroelectric local field is obtained.

[0019] The ferroelectric layer solution is prepared by dissolving polyvinylidene fluoride and polytrifluoroethylene ferroelectric polymer powders in diethyl carbonate at a molar ratio of 70:30 to obtain a poly(vinylidene fluoride-trifluoroethylene) solution with a mass ratio of 2-3%. The poly(vinylidene fluoride-trifluoroethylene) solution is spin-coated and then baked at a temperature of 110-120° C. for 10-20 min. The spin-coating-baking is then repeated, and the final baking temperature is 130-140° C. for 3-5 h to finally obtain a ferroelectric layer of target thickness.

[0020] The above-mentioned one-dimensional / two-dimensional heterojunction photodetector regulated by ferroelectric local field is applied in the detection of visible light and infrared bands. The ferroelectric local field application method is as follows: a constant source-drain voltage of 0.1~2V is applied to the electrode, and a voltage continuously changing from 0V to -80V is applied to the top gate transparent electrode layer, with an interval of -0.01~-5V.

[0021] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a one-dimensional / two-dimensional heterojunction photodetector regulated by a ferroelectric local field. The photodetection performance is regulated by the strong ferroelectric local field regulation of ferroelectric materials. When a negative voltage is applied to the top gate, the ferroelectric layer is polarized upward, generating a strong ferroelectric local field, depleting the carriers in the channel, so that the detector has the advantages of low dark current, high responsivity and wide spectrum detection with high detection rate. The polarization state plays an important role in modulating the built-in electric field of the van der Waals heterojunction. High-performance detection in the visible to infrared bands is achieved through ferroelectric regulation, broadening the use scenarios of the detector. At the same time, the residual polarization of the ferroelectric material can be stably maintained, that is, the detector does not need to apply an external gate voltage all the time when working, thereby reducing energy consumption. The technical problems of large dark current, low responsivity and low detection rate of existing infrared detectors are solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a structural cross-sectional view of the photodetector of the present invention; Figure 2 A top view of a photoelectric detector example of the present invention; Figure 3 This is an optical microscope image of a top view of the photodetector of Example 1 of the present invention; Figure 4 The electrical characteristic curves of the photodetector according to the embodiment of the present invention are in the state of ferroelectric local field regulation and in the state of no ferroelectric local field regulation; Figure 5 The photoelectric current rheological diagram of the photoelectric detector of the embodiment of the present invention under light of different wavelengths; Figure 6 A relationship diagram of the detection / responsivity-incident light power of the photoelectric detector of an embodiment of the present invention at different wavelengths; Figure 7 This is a performance comparison diagram of the detection / responsivity of the photodetector of the embodiment of the present invention at a wavelength of 532nm and that of the comparative example; Figure 8 This is a diagram showing the application of the photoelectric detector according to an embodiment of the present invention in image sensing and imaging; Fig. 9 This is a structural cross-sectional view of comparative example 1.

[0023] In the figure: 1-SiO2 / Si substrate, 2-one-dimensional Te nanowire layer, 3-two-dimensional MoS2 layer, 4-electrode, 5-ferroelectric layer, 6-transparent conductive layer. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0025] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be another element centered thereon. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be another element centered thereon at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0027] The drawings are only for illustrative purposes and should not be construed as limiting the present invention. To better illustrate the present embodiment, some parts in the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions may be omitted in the drawings. The positional relationships described in the drawings are only for illustrative purposes and should not be construed as limiting the present invention.

[0028] The specific implementation of the present invention is described in detail below with reference to the accompanying drawings: The present invention is a one-dimensional / two-dimensional heterojunction photodetector regulated by a ferroelectric local field. Figure 1 and Figure 2As shown, the detector includes a SiO2 / Si substrate 1, and a one-dimensional Te nanowire layer 2 as a P-terminal is arranged on the upper surface of the SiO2 / Si substrate 1; a two-dimensional MoS2 layer 3 as an N-terminal is arranged on the upper surface of the one-dimensional Te nanowire layer 2; an electrode 4 is arranged on one end of the upper surface of the one-dimensional Te nanowire layer 2 and one end of the upper surface of the two-dimensional MoS2 layer 3 respectively; a ferroelectric layer 5 is arranged on the upper surfaces of the one-dimensional Te nanowire layer 2 and the two-dimensional MoS2 layer 3; a transparent conductive layer 6 is arranged on the upper surface of the ferroelectric layer 5 as a top gate. Among them, one end of the two-dimensional MoS2 layer 3 is arranged on the upper surface of the one-dimensional Te nanowire layer 2, and the other end is arranged on the lower surface of the electrode 4; one end of the one-dimensional Te nanowire layer 2 is arranged on the lower surface of the two-dimensional MoS2 layer 3, and the other end is arranged on the lower surface of the electrode 4; the transparent conductive layer 6 does not contact the electrode 4.

[0029] The principle of the present invention is that when the top gate applies a negative voltage to polarize the ferroelectric layer, the generated ferroelectric local field acts on the Te / MoS2 heterojunction channel, adjusts the channel carrier concentration, effectively reduces the channel dark current, improves the photoelectric response and detection, and improves the detection response rate and detection rate of the device from visible light to near-infrared bands. Due to the non-volatility of ferroelectric materials, the ferroelectric local field always acts on the channel.

[0030] Example 1 A method for preparing a one-dimensional / two-dimensional heterojunction photodetector regulated by a ferroelectric local field comprises the following steps: See also Figure 1 and Figure 2 As shown, S1. The commercial SiO2 / Si wafer is cut into small pieces of 1 cm x 1 cm, and ultrasonically cleaned in acetone, isopropanol, and deionized water for 15 min in sequence, and then blown dry with nitrogen to obtain SiO2 / Si substrate 1, the thickness of the SiO2 layer is 280 nm, and the Si substrate (as a back gate) is lightly N-type doped silicon; The MoS2 crystal material and the graphene crystal material are respectively peeled off onto the PDMS substrate by mechanical peeling method to obtain MoS2 nanosheets and graphene nanosheets; Te nanowire material is grown on the substrate by CVD method, PDMS is attached to the Te nanowire material, and then separated to obtain a single Te nanowire on the PDMS; The growth method of Te nanowire material is CVD method. Te powder and SiO2 / Si substrate are placed in CVD device, and Ar / H2 mixed gas is ventilated at the same time. The Ar flow rate is 100 sccm, the H2 flow rate is 40 sccm, and it is heated at 750℃ for 20 min. Then it is naturally cooled to room temperature. A large amount of Te nanowire material can be obtained on SiO2 / Si substrate. S2. Find the one-dimensional Te nanowires and MoS2 nanosheets on the PDMS through the micro-focus transfer system, and use the dry transfer technology to transfer the Te nanowires to the upper surface of the SiO2 / Si substrate 1 to form a one-dimensional Te nanowire layer 2; and move the PDMS substrate with the MoS2 nanosheets to the top of the one-dimensional Te nanowire layer 2, reduce the adhesion to cover part of the Te nanowires, and obtain a two-dimensional MoS2 layer 3, forming a one-dimensional / two-dimensional heterojunction as the channel of the device; Thermally evaporate gold electrodes to transfer electrodes 4 to the upper surfaces of the two ends of the one-dimensional Te nanowire layer 2 and the two-dimensional MoS2 layer 3, respectively, as the source and drain of the device; S3. The ferroelectric layer was prepared by a spin coating - baking process, where a poly (vinylidene fluoride - trifluoroethylene) solution was spin coated onto the upper surface of the one-dimensional Te nanowire layer 2 and the two-dimensional MoS2 layer 3, and then dried to obtain a ferroelectric layer 5; The poly(vinylidene fluoride-trifluoroethylene) solution is a ferroelectric polymer powder of poly(vinylidene fluoride-trifluoroethylene) with a molar ratio of 70:30, which is dissolved in diethyl carbonate at a mass ratio of 2.5%. After spin coating the poly(vinylidene fluoride-trifluoroethylene) solution, the baking temperature is 115°C for 15 min, and then the spin coating-baking is repeated 4 times, and the final baking temperature is 135°C for 4 h, and finally a ferroelectric layer 5 with a thickness of 500 nm is obtained.

[0031] S4. Find the graphene nanosheet on the PDMS through the micro-focus transfer system, and move the PDMS substrate with the graphene nanosheet to the top of the one-dimensional Te nanowire layer 2 and the two-dimensional MoS2 layer 3, lower the fit so as to cover the ferroelectric layer 5, and cover the one-dimensional Te nanowire layer 2 and the two-dimensional MoS2 layer 3, but not contact the electrode 4, to obtain a transparent conductive layer 6. Finally, a one-dimensional / two-dimensional heterojunction photodetector regulated by a ferroelectric local field is obtained, such as Figure 3 shown.

[0032] The one-dimensional Te nanowire layer 2 has a diameter of 70 nm and a length of 20 μm.

[0033] The thickness of the two-dimensional MoS2 layer 3 is 8 nm, and the length and width are about 20 μm.

[0034] The length of the heterojunction portion where the one-dimensional Te nanowire layer 2 and the two-dimensional MoS2 layer 3 overlap is 11 μm.

[0035] The thickness of the gold electrode is 100 nm.

[0036] The ferroelectric layer is a poly (vinylidene fluoride-trifluoroethylene) film with a thickness of 500 nm.

[0037] The transparent conductive layer material is a graphene thin layer with a thickness of 8 nm.

[0038] Example 2 Different from Example 1, the ferroelectric layer 5 is a two-dimensional layered copper indium phosphorus sulfur material (CuInP2S6) with a thickness of 15nm; the transparent conductive layer 6 is Al with a thickness of 5nm, and the preparation method is to obtain an aluminum film by thermal evaporation. A one-dimensional / two-dimensional heterojunction photodetector regulated by a ferroelectric local field is obtained.

[0039] Comparative Example 1 The difference from Example 1 is that the preparation process of Comparative Example 1 does not include the step of spin coating the ferroelectric layer 5 and the transparent conductive layer 6, and the rest is the same as Example 1, to obtain a one-dimensional / two-dimensional heterojunction photodetector having a structure as shown in FIG. Fig. 9 shown.

[0040] The ferroelectric local field application method of the one-dimensional / two-dimensional heterojunction photodetector of Example 1 is as follows: a constant source-drain voltage of 0.1V is applied to the electrode, and a continuously changing voltage is applied to the top gate transparent electrode layer, the voltage ranges from 0V to -80V, and the interval is -0.5V. The photodetectors of Example 1 and Comparative Example 1 are tested, and the results are shown in detail. Figures 4 to 8 .

[0041] Figure 4 The electrical volt-ampere characteristic curve of the one-dimensional / two-dimensional heterojunction photodetector prepared in Example 1 of the present invention under the ferroelectric local field regulation state and without the ferroelectric local field regulation, the source-drain voltage range is -1.0V~1.0V, and no voltage is applied to the back gate. Figure 4 It can be seen that when the ferroelectric local field is regulated, the dark current is suppressed and reduced by 4 orders of magnitude. Correspondingly, as a detector, the dark current decreases in this state, indicating that the ferroelectric local field can effectively regulate the electrical properties of the heterojunction.

[0042] Figure 5 The photoelectrorheological diagram of the one-dimensional / two-dimensional heterojunction photodetector prepared in Example 1 of the present invention under different wavelengths of light, with wavelengths of 375nm, 405nm, 532nm, 1064nm, and 1550nm, source-drain voltage of 0.1V, back-gate voltage of -40V, and light intensity of 500 mW / cm 2 ,from Figure 5 It can be seen that the device has a good photocurrent response to light of each wavelength.

[0043] Figure 6 The relationship between the detection / responsivity and incident light power of the one-dimensional / two-dimensional heterojunction photodetector prepared in Example 1 of the present invention at different wavelengths is shown in FIG. Figure 5 The corresponding detection and responsivity are calculated from the data. At a wavelength of 532nm, the responsivity reaches 102 A / W and the detection is 3.1x10 14 Jones.

[0044] Figure 7 The performance comparison diagram of the detection / responsivity of the one-dimensional / two-dimensional heterojunction photodetector prepared in Example 1 of the present invention at a wavelength of 532nm and that of the comparative example 1 is shown in FIG. 1 . The source-drain voltage is 0.5V, the back gate voltage is -40V, and the responsivity reaches 10 4 A / W is about 3 orders of magnitude higher than that of the detector in comparative example 1 without ferroelectric local field regulation. The present invention greatly improves the detection performance of the device.

[0045] Figure 8 This is an application diagram of the one-dimensional / two-dimensional heterojunction photodetector in image sensing and imaging according to Example 1 of the present invention. A 532nm laser is irradiated onto the detector, and a signal generator is used to provide the laser with an image encoding signal. In this case, the image provided is a "PD" image. The test source-drain voltage is 0.1V, the back gate voltage is -50V, and the light intensity is 200 mW / cm 2 The detector detects the photocurrent change, senses the laser signal, measures the corresponding current value, and obtains the input image signal. The detector of the present invention can be used in information image transmission and other aspects.

Claims

1. A one-dimensional / two-dimensional heterojunction photodetector regulated by a ferroelectric local field, characterized in that: The invention comprises a SiO2 / Si substrate (1), wherein a one-dimensional Te nanowire layer (2) as a P-terminal is arranged on the upper surface of the SiO2 / Si substrate (1); a two-dimensional MoS2 layer (3) as an N-terminal is arranged on the upper surface of the one-dimensional Te nanowire layer (2); electrodes (4) are arranged at one end of the upper surface of the one-dimensional Te nanowire layer (2) and at one end of the upper surface of the two-dimensional MoS2 layer (3); ferroelectric layers (5) are arranged on the upper surfaces of the one-dimensional Te nanowire layer (2) and the two-dimensional MoS2 layer (3); the ferroelectric layer (5) completely covers or partially covers the electrode (4), and a transparent conductive layer (6) is arranged on the upper surface of the ferroelectric layer (5); One end of the two-dimensional MoS2 layer (3) is arranged on the upper surface of the one-dimensional Te nanowire layer (2), and the other end is arranged on the lower surface of the electrode (4); one end of the one-dimensional Te nanowire layer (2) is arranged on the lower surface of the two-dimensional MoS2 layer (3), and the other end is arranged on the lower surface of the electrode (4); and the transparent conductive layer (6) is not in contact with the electrode (4).

2. The one-dimensional / two-dimensional heterojunction photodetector controlled by ferroelectric local field according to claim 1, characterized in that: The SiO2 / Si substrate (1) has a structure in which a Si layer has a SiO2 layer on the upper surface, wherein the thickness of the SiO2 layer is 280-320 nm.

3. The one-dimensional / two-dimensional heterojunction photodetector controlled by ferroelectric local field according to claim 1, characterized in that: The diameter of the one-dimensional Te nanowire layer (2) is 50-150 nm.

4. The one-dimensional / two-dimensional heterojunction photodetector controlled by ferroelectric local field according to claim 1, characterized in that: The thickness of the two-dimensional MoS2 layer (3) is 5-20 nm.

5. The one-dimensional / two-dimensional heterojunction photodetector controlled by ferroelectric local field according to claim 1, characterized in that: The material of the electrode (4) is gold, silver or aluminum; the thickness of the electrode (4) is 50-100 nm.

6. The one-dimensional / two-dimensional heterojunction photodetector controlled by ferroelectric local field according to claim 1, characterized in that: The material of the ferroelectric layer (5) is a poly(vinylidene fluoride-trifluoroethylene) film or a two-dimensional layered copper indium phosphorus sulfur material (CuInP2S6); when the material of the ferroelectric layer (5) is a poly(vinylidene fluoride-trifluoroethylene) film, the thickness is 300-500 nm; when the material of the ferroelectric layer (5) is a two-dimensional layered copper indium phosphorus sulfur material (CuInP2S6), the thickness is 10-20 nm.

7. The one-dimensional / two-dimensional heterojunction photodetector controlled by ferroelectric local field according to claim 1, characterized in that: The material of the transparent conductive layer (6) is a graphene thin layer or an aluminum film; the thickness of the transparent conductive layer (6) is 5-20 nm.

8. A method for preparing a one-dimensional / two-dimensional heterojunction photodetector controlled by a ferroelectric local field according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. The MoS2 crystal material and the transparent conductive layer material are respectively peeled off onto the PDMS substrate by mechanical peeling method to obtain MoS2 nanosheets and transparent conductive layer nanosheets; Te nanowire material is grown on the substrate by CVD method, PDMS is bonded to the Te nanowire material, and then separated to obtain a single Te nanowire on the PDMS; S2. Use a microscopic focus transfer system to find the one-dimensional Te nanowires and MoS2 nanosheets on the PDMS, and transfer the Te nanowires to the upper surface of the SiO2 / Si substrate to form a one-dimensional Te nanowire layer (2); and move the PDMS substrate with the MoS2 nanosheets to the top of the one-dimensional Te nanowire layer (2) to cover part of the Te nanowires, thereby obtaining a two-dimensional MoS2 layer (3), thereby forming a one-dimensional / two-dimensional heterojunction as a channel of the device; The electrodes (4) are respectively transferred to the upper surfaces of the one-dimensional Te nanowire layer (2) and the two-dimensional MoS2 layer (3) to serve as the source and drain of the device; S3. The ferroelectric layer (5) is prepared by a spin coating-baking process, wherein the ferroelectric layer solution is spin-coated onto the upper surface of the one-dimensional Te nanowire layer (2) and the two-dimensional MoS2 layer (3), and then dried to obtain the ferroelectric layer (5); S4. The transparent conductive layer nanosheets on the PDMS are found by the microscopic focusing transfer system, and the PDMS substrate with the transparent conductive layer nanosheets is moved to the top of the one-dimensional Te nanowire layer (2) and the two-dimensional MoS2 layer (3), and covered on the ferroelectric layer (5). At the same time, the one-dimensional Te nanowire layer (2) and the two-dimensional MoS2 layer (3) are covered, but not in contact with the electrode (4), to obtain a transparent conductive layer (6); finally, a one-dimensional / two-dimensional heterojunction photodetector regulated by a ferroelectric local field is obtained.

9. The preparation method according to claim 8, characterized in that: The ferroelectric layer solution is prepared by dissolving polyvinylidene fluoride and polytrifluoroethylene ferroelectric polymer powders in diethyl carbonate at a molar ratio of 70:30 to obtain a poly(vinylidene fluoride-trifluoroethylene) solution with a mass ratio of 2-3%. The poly(vinylidene fluoride-trifluoroethylene) solution is spin-coated and then baked at a temperature of 110-120°C for 10-20 min. The spin-coating-baking is then repeated, and the final baking temperature is 130-140°C for 3-5 h to finally obtain a ferroelectric layer (5) of target thickness.

10. Application of the one-dimensional / two-dimensional heterojunction photodetector regulated by the ferroelectric local field according to any one of claims 1 to 7 in detection of visible light and infrared bands, characterized in that: The ferroelectric local field application method is: a constant source-drain voltage of 0.1~2V is applied to the electrode, and a voltage continuously changing from 0V to -80V is applied to the transparent electrode layer with an interval of -0.01~-5V.

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